Conventionally, there has been widely used a disk device which is installed with a magazine for housing disks and in which a disk taken out from the magazine is automatically played. Such a disk device is excellent in operability since the disks do not have to be inserted or ejected one by one every time when playing the disk.
However, it is required that the magazine attached or detached with respect to the device be strong enough to protect a plurality of disks held therein when taking out the magazine to the outside. Therefore, the walls of the magazine main body are thick, and as a result the sizes of the magazine itself and the entire device for installing the magazine are large. Moreover, in order to take out a tray or the like holding the disks inside the magazine, a guiding groove and a rail section are provided on an inner face of a side wall of the magazine. By forming such a groove and rail section, the thickness of the magazine side wall further increases and the gap between each adjacent disk holder becomes wide, whereby the height of the magazine increases and the size of the device for installing the magazine also increases.
In addition, in order to take out a disk housed in the magazine and play the disk, it is necessary to provide a sufficient space in the device, thus the size of the device increases. Particularly, as in an on-board disk device or the like, in the case where a disk needs to be housed in a size of 180×50 (mm), which is called “DIN size”, or a size of 180×100 (mm), which is called “double DIN size”, small-size disk devices are highly demanded.
In order to deal with such demand, a disk device is developed in which a magazine is split, and a drive unit for playing a disk is provided in a space formed by splitting the magazine, so that the disk can be played without taking out the disk from the magazine (see Japanese Patent Application Laid-Open No. H11-232753, Japanese Patent Application Laid-Open No. H11-306637). Such disk device does not require a space for taking out and play a disk, thus the size of the entire device can be made small.
Furthermore, there is proposed a disk device, in which a detachable magazine is not used but a disk holding section (a tray or the like) capable of holding a plurality of disks is incorporated in a stacked fashion, and a disk inserted from a disk insertion opening is automatically housed in the disk holding section, and the housed disk can be automatically ejected. In such a disk device, an opening, a mechanism and the like coping with the thickness of the magazine or attachment of the magazine are not required, thus a small-size device can be realized. Particularly, in the invention disclosed in Japanese Patent Application Laid-Open No. 2000-195134, trays are provided on a top and bottom so that they can be withdrawn as with the abovementioned split magazine, and a drive unit is inserted into a space formed between the trays, whereby a disk can be played without taking it out. Accordingly, further reduction in size of the device can be achieved.
Incidentally, in the conventional disk device using the disk holding section such as a tray or the like as described above, the tray, drive unit, and disk insertion opening need to be moved relatively in order to position a disk to be played or inserted/ejected. As a mechanism used for such purpose, use of a camp late having a sloping or step-like cam is considered. For example, a chassis or the like having a pin inserted into the cam of the cam plate is caused to hold the entire trays, whereby the chassis and the trays are moved up or down to desired positions respectively in accordance with a slide movement of the cam plate.
On the other hand, in order to stably hold a disk on a turning table when playing the disk, it is preferred that an inner diameter of the disk be pressed against the turning table by means of a clamper so as to sandwich the disk. For this reason, when playing the disk, the trays have to be withdrawn from the top and bottom to secure a sufficient space. As a mechanism for withdrawing the trays, use of the cam plate having the sloping or step-like cam is considered as described above. However, since it is difficult to use one type of cam plate to realize a plurality of functions such as positioning and splitting the trays as described above, a plurality of types of cam plates are disposed separately.
However, each of these cam plates needs to secure a required slide stroke, thus the size of a required space increases and the degree of freedom for disposing other members is limited in order to prevent an interference between the sliding cam plates. Moreover, each of the flat cam plates has a large contact area contacting with other member, and has to be slid by relatively strong drive power, thus even if the position of the tray, which is the object of selection, and the position of the cam of the cam plate are misaligned due to vibration, the misaligned positions cannot be corrected in the middle of operation.
In the conventional disk device using the disk holding sections such as trays or the like as described above, it is preferred to configure a structure in which the disks are securely held by the trays when housing the disks and a disk is easily released from the trays when playing or inserting/ejecting the disk. For this reason, for example, a holding member for holding disks on the trays is biased in a disk holding direction by a biasing member such as a spring when housing the disks, and a mechanism is provided for displacing this holding member against the bias force of the biasing member when playing or inserting/ejecting a disk.
However, for example, in the case where excellent resistance to vibration is requested as in the on-board disk device, if a disk is held on the tray simply by means of the bias force of the biasing member only, the position of the holding member is changed when strong vibration or the like occurs, destabilizing the position of the disk. In order to deal with such problem, if a mechanism or the like for fixing the holding member is provided separately when housing the disks, the size of the required space increases.
Particularly, the device is made complex and large by providing and accordingly synchronizing a mechanism for selecting a tray on which a desired disk is held, a mechanism for displacing the holding member in order to release the disk when playing or inserting/ejecting the disk, and a mechanism for locking the holding member when housing the disk.
The present invention is contrived in order to resolve the problems of the conventional technology as described above, and an object of the present invention is to provide a disk selecting device and a disk device in which only a small space is necessary and which can reliably prevent an erroneous selection of a disk.